The ABC transporters are a large family of conserved proteins that transport a wide variety of molecules across cellular membranes. ABCA1 is a member of the ABCA subfamily, which acts as a lipid translocator. The molecule was originally identified as a scavenger receptor on macrophages and research shows that ABCA1 also plays a major role in cholesterol metabolism. ABCA1 may play an important role in protecting against cardiovascular disease. Mutations in ABCA1 gene have been associated with Tangiers disease, a genetic disorder of lipid metabolism, and familial high density lipoprotein (HDL) deficiency.